e THE USE OF REMOTE SENSING AND GIS IN MONITORING
TROPICAL RAIN FOREST
y, Falls Yousif Ali Hussin Shahzanan R. Shaker Leo Pantimena
The International Institute for Aerospace Survey
and Earth Sciences (ITC), Enschede, The Netherlands
E-mail: HUSSIN@ITC.NL, Fax: (31)(53)4874-399
KEY WORDS: Optical, Radar, Remote Sensing, GIS, Tropical Forest, Deforestation
ABSTRACT:
The demand for timely and accurate geographic information has accelerated greatly for a number of earth
related fields including natural resource management and exploitation, urban and regional planning,
development of industry and agriculture, and geological exploitation. Geographic information can be derived
easily from the remotely sensed data. All remote sensing data used the optical portions of the electromagnetic
spectrum as its own source of energy has experienced two kinds of limitations. First, if cloud cover is
present, data can not be obtained using sensors operating in those wavelength regions. Second, the spectral
regions sampled do not always provide sufficient information to differentiate between various forest or other
agricultural and cultural cover types. Radar data, which utilizes the active microwave portion of the
spectrum, can provide important additional information about terrain surfaces and forest and agricultural
plants canopies. Satellite remote sensing often used to obtain information on actual land cover land use and
to monitor changes in the regions with often cloudy conditions in the microwave range. The main objective
of this research was to monitor tropical rain forest land use changes in two Indonesian test sites using multi-
temporal ERS-1 and JERS-1 radar data and optical Landsat TM, MSS and Spot XS data.
1. INTRODUCTION depletion which reduced crop production. In order
to manage and control the hazard land use
Forest resources are important socially, changes, especially in tropical countries in heavily
economically and environmentally. For many populated areas, it is essential to monitor these
years the problems of deforestation in the tropical changes.
rain forest had raised considerable international
interest. Degradation is another existing way of Given the importance of the tropical forest issue in
tropical rain forest destruction. From 1850-1980 terms of biodiversity, climate, biochemical cycles
about 15% of the earth’s forest cover disappeared and economic development, there is a need of
as a result of human activities (World Resources concentrated effort to find the best and effective
Institute 1987), according to this report the tropical type of remotely sensed data and then develop i
rain forest of Asia, Africa, and South America effective utilization of this data in an operational
declined by 27 percent. This depletion is very forest monitoring program.
significant, where about 2.5 billion people depend
on natural forest resources for many economic and In the twentieth century, the demand for timely
environmental goods and services. According to and accurate geographic information has
the Food and Agriculture Organization of the accelerated greatly for a number of earth related
United Nation report of 1988, between 1980 and fields including monitoring tropical rain forest
1985 the estimated annual rate of tropical forest conditions. Geographic information can be
degradation was 0.6 percent or 11.4 million derived easily from the remotely sensed data such
hectares. The major causes of this degradation in as: aerial photographs, Multispectral Scanner
the tropics are agriculture expansion, overgrazing, (MSS) using aircraft or spacecraft, Landsat
fuelwood gathering, and logging. Behind all these Thematic Mapper (TM), SPOT Panchromatic and
causes 1s the population growth. In general, high MSS, AVHRR NOAA, etc. All remote sensing
population pressure has its impacts on the tropical data used the optical portions of the
forest land use and its changes. These changes are electromagnetic spectrum as its own source of
mostly either because of the urban expansion in energy has experienced two kinds of limitations.
the , or the farmers want to change the farming First, if cloud cover is present, data can not be
System (e.g. from food crop to market or cash obtained using sensors operating in those
Crop). They could also be due to multiple or over wavelength regions. Second, the spectral regions
use of the land that resulted in soil fertility sampled do not always provide sufficient
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B7. Vienna 1996